空间插值法在降水分布中的应用

空间降水信息需求日益增加,应用于空间降水的插值方法也日益完善,不同的插值方法因为所应用的地区不同会产生不同的结果．对于不同的地区,应采用不同的方法进行比较,才能得出最佳的插值方法．采用江苏省的南京市、无锡市等１２个市自１９９９—２００８年间的１月 的降雨量为数据源,分别用普通克里格插值法（ＯＫ）和反距离加权法（ＩＤＷ）对同时期江苏省扬州市的降雨量进行插值,通过分析发现：普通克里格插值法的结果整体上优于反距离加权平均法．     

基于GIS技术的甘肃省气温空间分布特征

利用40 a气象站气温观测数据,结合GIS技术,建立甘肃省气温空间化模型,以高分辨率的DEM作为模型的输入参数实现气温数据的空间化,同时与传统的气温内插方法 (反距离加权法(IDW)、克里格(Kriging)、协同克里格(Co-Kriging))的插值结果进行比较分析,结果反映利用多元回归分析+克里格方法建立的气温数据栅格化结果较好,比传统的气温内插方法插值精度高,插值结果很好的再现了原始测量结果。     

基于GIS气象要素空间插值方法在巴彦淖尔市冬季公路的养护应用

针对内蒙古自治区巴彦淖尔市气象站点分布情况,以2000—2009年9个气象站点(临河,杭锦后旗,五原,磴口,乌拉特前、中、后三旗,海力素,大佘太)的年平均降水和温度为基础数据,通过GIS空间分析中的空间数据插值方法,分别建立平均降水和温度与海拔、经纬度之间的回归方程;在此基础上,建立模拟站点来增加气象数据的信息量。分别采用反距离加权法、径向基函数法、趋势面分析和普通克里格法几种插值方法进行比较插值分析。误差分析表明没有绝对最优的空间插值方法,只有在特定的条件下的最有效方法,对于降水量插值来说三次样条小波插值法是最好的;比较分析的结果表明,模拟站点的加入大大提高了插值的精度,普通克里格法比反距离加权法和径向基函数法具有更为理想的插值效果;并据此理论分析对空间插值在冬季高速公路养护方面的应用问题进行阐述。     

复杂山地环境下气候要素空间插值精度比较研究

空间插值可以提供每个计算栅格的气候要素资料,该文运用反距离加权插值法（IDW）、普通克里格插值法、薄盘光滑样条函数拟合法3种空间插值方法,对1971--2000年西南地区复杂山地环境下92个气象站点温度、降水以及相对湿度的各月气候平均值和多年平均值进行了空间插值。并进行了交叉验证和随机站点验证,运用绝对平均误差（MAE）、相对平均误差（MRE）及均方根误差（RMSE）作为插值精度检验的标准。结果表明：插值方法中,薄盘光滑样条函数插值法在山地环境下对3种气象要素的插值精度是最优的,特别是对于温度和降水,而对于相对湿度3种方法差别不大,都可以满足精度要求;在时间尺度上,对于温度相对较低、降水量相对较小的冬季,3种插值方法插值精度都相对于夏季和年平均明显较差,相对湿度插值精度季节差异不明显。     

贺州市丘陵区降雨量的空间插值方法比较

以2012—2021年贺州市113个自动气象站年平均降雨量数据为基础,基于GIS技术,选取反距离权重插值方法（IDW）、普通克里金插值方法（OK）、协同克里金插值方法（CK）、径向基函数插值方法（RBF）、局部多项式插值方法（LPI）和经验贝叶斯克里金插值方法（EBK）,分别对贺州市多年年平均降雨量进行空间插值,对插值结果进行交叉检验和误差分析。结果表明,在考虑贺州市多年平均降雨量的上下限和空间分布特征,局部多项式插值方法（LPI）插值效果最好,能较为真实地表现贺州市多年平均降雨量空间分布特征。贺州市多年平均降雨量的分布特点为自东北向西南逐渐增多,受地形地貌影响,其年平均降雨量最大值主要位于贺州市昭平县。     

综合分析法在复杂地形气温精细格点化中的应用

基于高分辨数值模式预报、数字高程模型和区域自动站逐时气温观测资料,以兼具平原、丘陵、盆地、山地、海岛和海洋等复杂地形的浙江省为研究区域,建立了适用于该地区的综合分析方法,并将该方法与反距离加权插值法、普通克里格插值法和考虑高程的反距离加权插值法进行比较。结果表明:综合分析法能给出最优的格点化温度分析场,考虑高程的反距离加权法其次,最后是反距离加权法和普通克里格法。考虑高程的反距离加权插值法和综合分析法对高海拔无测站区域气温的重建有较为明显的优势。综合分析法获取的温度分析场在山地、海岛和海洋等资料稀少或缺测的复杂地形区域仍旧能保持合理的空间分布状态,对复杂地形资料稀少或缺测地区的插补能力有突出优势。温度资料格点化精度随站点数增加而提高,且当站点数达到一定数值后,精度趋于稳定;综合分析法在站点数达到1000个(站点平均间距约16 km)后就趋于稳定,而其余三种方法在站点数增加到1600个(站点平均间距约13 km)后趋于稳定。     

基于雷达校正的雨量插值研究

自动站点雨量数据到格点化雨量数据的插值方法一直在气象业务中有着重要应用,但传统插值法一般只考虑距离对估测点的影响,不能够真实地反应降水的落区分布.利用多普勒雷达资料对雨量插值结果进行校正,可使得插值后的结果较好地反映雷达反射率分布特征,也可以较好地克服反距离加权插值法的尖点问题.经过业务测试检验,基于雷达校正的雨量插值方法效果较为稳定,可以在业务中进行应用.     

基于GIS的新疆多年平均降水量空间插值精度比较研究

以新疆具有完整资料的90个气象站点中的75个站点的基本地理信息和1995—2008年平均降水数据资料为基础,以ArcGIS为数据处理平台,分别采用反距离加权法、径向基函数法、克里格法、协克里金方法对全疆降水空间分布进行插值,并通过没有参与插值的15个气象站点的实际降水量与插值结果进行相对误差分析,研究结果表明:在年降水量插值的4种算法中,普通克里格法(Kriging)的计算精度最高。利用最优的插值方法的栅格降水空间数据库,建立的多年降水资源信息系统,可快速计算研究区内任一地域单元中降水的总量及其空间变化,对降水资源模拟、工程规划、发展战略及决策管理,均具有重要的意义。     

陕西苹果主产区日最低(最高)气温的空间插值

分考虑海拔高度对气温的影响和不考虑海拔高度对气温的影响两种情况,用反距离权重法、样条法、普通克里格法对日最低气温和日最高气温空间插值,并对插值的结果交叉检验,结果表明,考虑海拔高度对气温影响下的普通克里格插值法是诸多方法中的最佳选择。     

浙江地区雷暴日插值方法及分布特性的研究

常用的空间插值方法主要有反向距离加权法、样条函数法和克里金插值法等,本文对浙江区域内的68个气象站点的43 a平均雷暴日数据进行空间插值试验,通过对插值结果的交叉验证来比较分析得出了浙江区域范围内雷暴日插值的优选方法。最后利用优选方法的插值结果结合浙江地形条件对浙江地区雷暴日的分布特性进行了分析。     

CHARACTERISTICS AND TRENDS OF CLIMATIC EXTREMES IN CHINA DURING 1959–2014

The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics.     

Could the Recent Taal Volcano Eruption Trigger an El Ni?o and Lead to Eurasian Warming?

正The Taal Volcano in Luzon is one of the most active and dangerous volcanoes of the Philippines. A recent eruption occurred on 12 January 2020(Fig. 1a), and this volcano is still active with the occurrence of volcanic earthquakes. The eruption has become a deep concern worldwide, not only for its damage on local society, but also for potential hazardous consequences on the Earth's climate and environment.     

VARIABILITY OF INTER-ANNUAL RELATIONSHIP BETWEEN INDIAN OCEAN DIPOLE AND HUAXI REGION’S AUTUMN PRECIPITATION

The moving-window correlation analysis was applied to investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the synchronous autumn precipitation in Huaxi region, based on the daily precipitation, sea surface temperature (SST) and atmospheric circulation data from 1960 to 2012. The correlation curves of IOD and the early modulation of Huaxi region’s autumn precipitation indicated a mutational site appeared in the 1970s. During 1960 to 1979, when the IOD was in positive phase in autumn, the circulations changed from a “W” shape to an ”M” shape at 500 hPa in Asia middle-high latitude region. Cold flux got into the Sichuan province with Northwest flow, the positive anomaly of the water vapor flux transported from Western Pacific to Huaxi region strengthened, caused precipitation increase in east Huaxi region. During 1980 to 1999, when the IOD in autumn was positive phase, the atmospheric circulation presented a “W” shape at 500 hPa, the positive anomaly of the water vapor flux transported from Bay of Bengal to Huaxi region strengthened, caused precipitation ascend in west Huaxi region. In summary, the Indian Ocean changed from cold phase to warm phase since the 1970s, caused the instability of the inter-annual relationship between the IOD and the autumn rainfall in Huaxi region.     

ANALYSIS OF “BIMODAL PATTERN” STORM ACTIVITY CHARACTERISTICS OF THE BAY OF BENGAL

Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms.     

LOW-FREQUENCY CIRCULATION AND EXTENDED-RANGE FORECAST IN CONNECTION WITH AUTUMN EXTREME HEAVY RAINFALL PROCESS IN HAINAN

Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn (referred to as EHRPs) and 10–30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2 (CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10–30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the ‘north high (cold), south low (warm)’ pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough, consequently leading to EHRPs. Considering the link between low-frequency circulation and EHRPs, a low-frequency wave train index (LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015–2016 indicate that EHRPs can be predicted 8–24 d in advance, with an average period of validity of 16.7 d.     

AN ATTRIBUTION ANALYSIS OF CHANGES IN POTENTIAL EVAPOTRANSPIRATION IN THE BEIJING–TIANJIN–HEBEI REGION UNDER CLIMATE CHANGE

Based on the measurements obtained at 64 national meteorological stations in the Beijing–Tianjin–Hebei (BTH) region between 1970 and 2013, the potential evapotranspiration (ET0) in this region was estimated using the Penman–Monteith equation and its sensitivity to maximum temperature (Tmax), minimum temperature (Tmin), wind speed (Vw), net radiation (Rn) and water vapor pressure (Pwv) was analyzed, respectively. The results are shown as follows. (1) The climatic elements in the BTH region underwent significant changes in the study period. Vw and Rn decreased significantly, whereas Tmin, Tmax and Pwv increased considerably. (2) In the BTH region, ET0 also exhibited a significant decreasing trend, and the sensitivity of ET0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET0 was most sensitive to Pwv in the fall and winter and Rn in the spring and summer. On the annual scale, ET0 was most sensitive to Pwv, followed by Rn, Vw, Tmax and Tmin. In addition, the sensitivity coefficient of ET0 with respect to Pwv had a negative value for all the areas, indicating that increases in Pwv can prevent ET0 from increasing. (3) The sensitivity of ET0 to Tmin and Tmax was significantly lower than its sensitivity to other climatic elements. However, increases in temperature can lead to changes in Pwv and Rn. The temperature should be considered the key intrinsic climatic element that has caused the "evaporation paradox" phenomenon in the BTH region.     

Revisiting the Concentration Observations and Source Apportionment of Atmospheric Ammonia

正While China’s Air Pollution Prevention and Control Action Plan on particulate matter since 2013 has reduced sulfate significantly, aerosol ammonium nitrate remains high in East China. As the high nitrate abundances are strongly linked with ammonia, reducing ammonia emissions is becoming increasingly important to improve the air quality of China. Although satellite data provide evidence of substantial increases in atmospheric ammonia concentrations over major agricultural regions, long-term surface observation of ammonia concentrations are sparse. In addition, there is still no consensus on     

全球贸易隐含碳变化及其影响分析

基于最新的GTAP8 (Global Trade Analysis Project）数据库,使用投入产出法,分析了2004年到2007年全球贸易变化下南北集团贸易隐含碳变化及对全球碳排放的影响。结果显示,随着发展中国家进出口规模扩张,全球贸易隐含碳流向的重心逐渐向发展中国家转移。2004年到2007年,发达国家高端设备制造业和服务业出口以及发展中国家资源、能源密集型行业及中低端制造业出口的趋势加强,该过程的生产转移导致全球碳排放增长4.15亿t,占研究时段全球贸易隐含碳增量的63%。未来发展中国家的出口隐含碳比重还将进一步提高。贸易变化带来的南北集团隐含碳流动变化对全球应对气候变化行动的影响日益突出,发达国家对此负有重要责任。     

COMPARATIVE ANALYSIS OF VARIOUS DATA OF AIR–SEA TEMPERATURE DIFFERENCE AND ITS VARIATION ACROSS SOUTH CHINA SEA IN THE PAST 35 YEARS

Using the International Comprehensive Ocean-Atmosphere Data Set(ICOADS) and ERA-Interim data, spatial distributions of air-sea temperature difference(ASTD) in the South China Sea(SCS) for the past 35 years are compared,and variations of spatial and temporal distributions of ASTD in this region are addressed using empirical orthogonal function decomposition and wavelet analysis methods. The results indicate that both ICOADS and ERA-Interim data can reflect actual distribution characteristics of ASTD in the SCS, but values of ASTD from the ERA-Interim data are smaller than those of the ICOADS data in the same region. In addition, the ASTD characteristics from the ERA-Interim data are not obvious inshore. A seesaw-type, north-south distribution of ASTD is dominant in the SCS; i.e., a positive peak in the south is associated with a negative peak in the north in November, and a negative peak in the south is accompanied by a positive peak in the north during April and May. Interannual ASTD variations in summer or autumn are decreasing. There is a seesaw-type distribution of ASTD between Beibu Bay and most of the SCS in summer, and the center of large values is in the Nansha Islands area in autumn. The ASTD in the SCS has a strong quasi-3a oscillation period in all seasons, and a quasi-11 a period in winter and spring. The ASTD is positively correlated with the Nio3.4 index in summer and autumn but negatively correlated in spring and winter.     

Retrieval of outgoing longwave radiation from COMS narrowband infrared imagery

Hourly outgoing longwave radiation(OLR) from the geostationary satellite Communication Oceanography Meteorological Satellite(COMS) has been retrieved since June 2010. The COMS OLR retrieval algorithms are based on regression analyses of radiative transfer simulations for spectral functions of COMS infrared channels. This study documents the accuracies of OLRs for future climate applications by making an intercomparison of four OLRs from one single-channel algorithm(OLR12.0using the 12.0 μm channel) and three multiple-channel algorithms(OLR10.8+12.0using the 10.8 and 12.0 μm channels; OLR6.7+10.8using the 6.7 and 10.8 μm channels; and OLR All using the 6.7, 10.8, and 12.0 μm channels). The COMS OLRs from these algorithms were validated with direct measurements of OLR from a broadband radiometer of the Clouds and Earth's Radiant Energy System(CERES) over the full COMS field of view [roughly(50°S–50°N, 70°–170°E)] during April 2011.Validation results show that the root-mean-square errors of COMS OLRs are 5–7 W m-2, which indicates good agreement with CERES OLR over the vast domain. OLR6.7+10.8and OLR All have much smaller errors(～ 6 W m-2) than OLR12.0and OLR10.8+12.0(～ 8 W m-2). Moreover, the small errors of OLR6.7+10.8and OLR All are systematic and can be readily reduced through additional mean bias correction and/or radiance calibration. These results indicate a noteworthy role of the6.7 μm water vapor absorption channel in improving the accuracy of the OLRs. The dependence of the accuracy of COMS OLRs on various surface, atmospheric, and observational conditions is also discussed.